It has been known a composite working lathe for performing composite processing on a workpiece held at a workpiece spindle as having a mill tool.
Such a composite working lathe has an automatic tool changer (ATC), and composite processing is performed with a tool appropriate for the processing. The tool is set to a tool spindle by means of ATC.
For tool changing, the tool headstock is moved to an ATC location to automatically change tools. In a case where a processing position is distanced from the ATC location, a problem such as processing efficiency decreases because time for changing tools becomes long.
In disclosure of Patent documents in the following, tools for turning are attached on a tool headstock having a mill tool attached and a turret cutting tool rest is attached thereto.